1. Field of the Invention
The present invention relates to a flash photographing system for use in such as a camera.
2. Description of the Related Art
Heretofore, a camera which accomplishes the following automatic exposure controls are known. The following three exposure control modes are known:
(1) shutter-priority automatic exposure. Only a shutter speed is set in this mode. PA1 (2) aperture-priority automatic exposure. Only an aperture value is set in this mode. PA1 (3) program automatic exposure. No operation to set exposure factor is required in this mode.
The use of the camera which accomplishes such an automatic exposure control eliminates the need for performing a troublesome calculation for an exposure, namely, an easy-to-use camera. Further, whoever uses the camera can take a picture with an appropriate exposure amount set.
A camera is known which decides the brightness or luminance of an object, warns the photographer, when the object is dark, that the exposure time is so long that camera shake may occur using only ambient light, and informs the photographer flash should be emitted. Since the camera automatically detects whether or not a flash is required, the camera is easy to use.
According to the camera having a plurality of exposure controlling modes as described camera, it is necessary for the photographer to turn on the power switch in emitting a flash.
A camera disclosed in Japanese Utility Model Laid-Open Publication No. 88129/1986 incorporates a flash emitting device which emits a light automatically when the luminance of an object is less than a predetermined value. The camera is very convenient to use because a flash light is automatically emitted when an object is so dark that a camera may occur. However, since the camera has only a programmed automatic exposure mode, the photographer's intention, for example, to take a photograph in which a main object is emphasized with the depth of field small or to take a picture of the movement of an object with an exposure time set to be long, cannot be accomplished.